has用作第三人称单数形式。has具有吃、有、从事、允许等含义。had通常作动词have的过去式和过去分词,表示得到,也可以用于完成时和过去完成时,表示已经。
Have you any questions?这个have的意思是有,是实意动词
Do you have any questions?这个have的意思是有,也是实意动词
而do才是助动词
have只有在实意动词时,意思才为有
have在做情态动词时,充当的是助动词,无实际意义
1,动词,“有”的意思。
I have a book。我有一本书。
Do you have a book?
I don’t have a book。(也可以说I haven’t a book。不常用)
2,助动词。“使……”
have sb do 让某人做
have sb doing 让某人一直做
have sb/sth done 某人/某物被……
3,have to,“不得不,必须”,表示不是主观意愿
It’s dark outside,I have to go home。天黑了,我不得不回家。
Do you have to……。
I don’t have to……。
4,用于完成时
have+动词的过去分词
As Warrent's parents,you are to set a good example to him.(表责任,义务,相当于,must should) Are we to clean the corridor,Mrs Dell? (表征求意见=shall)
The temperature is to drop soon.(表示可能性)
Would she get cross if I were to sail into her of lying?(表假设)